|1.||(modifier) a piece of software designed to prevent viruses entering a computer system or network: antivirus software|
|2.||(modifier) of or relating to such a piece of software|
|—n , pl -ruses|
|1.||any of a group of submicroscopic entities consisting of a single nucleic acid chain surrounded by a protein coat and capable of replication only within the cells of living organisms: many are pathogenic|
|2.||informal a disease caused by a virus|
|3.||any corrupting or infecting influence|
|4.||computing an unauthorized program that inserts itself into a computer system and then propagates itself to other computers via networks or disks; when activated it interferes with the operation of the computer|
|[C16: from Latin: slime, poisonous liquid; related to Old English wāse marsh, Greek ios poison]|
virus vi·rus (vī'rəs)
n. pl. vi·rus·es
Any of various simple submicroscopic parasites of plants, animals, and bacteria that often cause disease and that consist essentially of a core of RNA or DNA surrounded by a protein coat. Unable to replicate without a host cell, viruses are typically not considered living organisms.
A disease caused by a virus.
Microorganisms consisting of DNA and RNA molecules wrapped in a protective coating of proteins. Viruses are the most primitive form of life. They depend on other living cells for their reproduction and growth. (See under “Medicine and Health.”)
Note: Viruses cause many diseases. (See viral infection.)
A minute organism that consists of a core of nucleic acid surrounded by protein. Viruses, which are so small that a special kind of microscope is needed to view them, can grow and reproduce only inside living cells. (See under “Life Sciences.”)
See computer virus.